How to select bearings?

There are many types of bearings, what issues need to be considered when choosing a bearing?

Today, PPH bearings will share with you the issues that need to be paid attention to when selecting bearings.

The main factors to consider when making a choice are as follows.

1. Load on bearings

The size, direction, and nature of the load on the bearing are the main criteria for selecting the type of bearing.

(1) Ball bearings should be selected for light and medium loads based on the size and nature of the load; Roller bearings should be selected for heavy loads or impact loads.

(2) Load direction

When subjected to pure radial load, deep groove ball bearings, cylindrical roller bearings, or needle roller bearings can be selected. When subjected to pure axial load, thrust bearings can be selected. When there are both radial and axial loads, if the axial load is not too large, deep groove ball bearings or angular contact ball bearings or tapered roller bearings with smaller contact angles can be selected; If the axial load is large, these two types of bearings with larger contact angles can be selected; If the axial load is large and the radial load is small, thrust angular contact bearings can be used, or a support structure consisting of radial bearings and thrust bearings can be used together.

2. Bearing speed

(1) Ball bearings should be given priority when driving at high speeds;

(2) When the inner diameter is the same, the smaller the outer diameter, the smaller the centrifugal force. Therefore, it is advisable to use ultra light and ultra light series bearings at high speeds.

(3) The maximum speed of thrust bearings is very low, and friction heating is severe during high-speed operation. If the axial load is not very large, angular contact ball bearings or deep groove ball bearings can be used to withstand pure axial force.

3. Heart adjustment requirements

When the centerline of the shaft does not coincide with the centerline of the bearing due to manufacturing and installation errors, or when the axis of the inner and outer rings of the bearing deviates due to the bending of the shaft under stress, it is advisable to use self-aligning ball bearings or self-aligning roller bearings.

4. Allowable space

When the radial space is limited, needle roller bearings or ultra light and ultra light diameter series bearings can be used. When the axial dimension is limited, bearings with smaller width dimensions, such as narrow or ultra narrow width series, can be selected.

5. Installation and disassembly

In machinery where the bearing seat is not divided but the bearing must be installed and removed along the axial direction, and where frequent installation and removal of bearings is required, bearings with separable inner and outer rings (such as Class 3, Class N, etc.) should be preferred; When the bearing is installed on the long shaft, for ease of assembly and disassembly, a bearing with a tapered inner ring can be selected (the second item in the rear code is K).

6. Tolerance grade

The tolerance level of dynamic bearings is divided into 6 levels: 0 level (ordinary level), 6 level, 6X level, 5 level, 4 level, and 2 level. Normal level is the lowest, level 2 is the highest. Ordinary level applications are the most widely used. For most machines, using bearings with zero tolerance is sufficient to meet the requirements, but for machine tool spindles, precision machinery, instruments, and high-speed rotating shafts with strict requirements for rotational accuracy, high-precision bearings should be selected.

The above is the content about bearing selection provided by PPH bearings for you. PPH bearings are always available to provide you with bearing related services.